mMRC dyspnea grade (Mahler 1988)

mMRC

Return the Mahler 1988 modified Medical Research Council (mMRC) dyspnea grade 0-4 from a caller-assigned integer, with the published grade wording.

LIVE $0.005 USDC GET /api/calc/mmrc

Markdown: /docs/mmrc.md · Canonical: https://magentlab.com/docs/mmrc

Not a medical device. Not a diagnosis, dose, or listing recommendation.

What it computes

Return the Mahler 1988 modified Medical Research Council (mMRC) dyspnea grade 0-4 from a caller-assigned integer, with the published grade wording.

When to use

When an agent needs the modified MRC 0-4 grade and must not invent GOLD ABE groups, a BODE index, or Bestall MRC grades 1-5.

When not to use

Not a medical device and not a diagnosis. magent does not examine the patient.
The caller assigns mMRC 0-4. magent does not interview the patient or apply a GOLD ABE group.
This is the modified MRC 0-4 scale (Mahler 1988). It is not Bestall MRC grades 1-5 and is not a BODE index.

Formula

modified MRC (mMRC) grade 0-4 as assigned by the caller; Mahler 1988 (not Bestall MRC 1-5)

Citation

Title: Evaluation of clinical methods for rating dyspnea
Authors: Mahler DA, Wells CK
Source: Chest. 1988;93(3):580-586
DOI: 10.1378/chest.93.3.580

Worked example

Grade 0 strenuous exercise only

Given: mmrc=0

mmrc 0 → breathless only with strenuous exercise; score 0; max 4

Also searched as

mMRC
modified MRC
modified Medical Research Council
mMRC dyspnea scale
Mahler dyspnea grade
MRC dyspnea 0-4
breathlessness grade
modified MRC grade

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/mmrc?mmrc=0

Full URL: https://api.magentlab.com/api/calc/mmrc?mmrc=0

Call

Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params return HTTP 400 before any quote or charge.

curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/mmrc?mmrc=0"

Parameters

Name	Type	Required	Description
`mmrc`	integer	required	Mahler 1988 modified MRC dyspnea grade 0-4 as assigned by the caller (0 breathless only with strenuous exercise; 1 short of breath when hurrying on the level or walking up a slight hill; 2 walks slower than people of the same age on the level because of breathlessness, or has to stop for breath when walking at own pace on the level; 3 stops for breath after walking about 100 yards or after a few minutes on the level; 4 too breathless to leave the house, or breathless when dressing or undressing). Not Bestall MRC 1-5. magent does not examine the patient.

Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

POST /api/calc/mmrc Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 PREVIEW

1 to 25 items. Each item uses the same keys as the GET query parameters.
POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request (fixture)

{
  "items": [
    {
      "mmrc": "0"
    },
    {
      "mmrc": "0"
    }
  ]
}

Open bulk paywall →

Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.

Example 200 (fixture)

{
  "count": 2,
  "path": "/api/calc/mmrc",
  "items": [
    {
      "description": "Breathless only with strenuous exercise",
      "components": [
        {
          "factor": "mmrc",
          "points": 0,
          "present": true
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Mahler DA, Wells CK",
        "doi": "10.1378/chest.93.3.580",
        "id": "mahler-1988",
        "pmid": "3342669",
        "source": "Chest. 1988;93(3):580-586",
        "title": "Evaluation of clinical methods for rating dyspnea"
      },
      "formula": "mmrc",
      "formula_expression": "modified MRC (mMRC) grade 0-4 as assigned by the caller; Mahler 1988 (not Bestall MRC 1-5)",
      "max_score": 4,
      "score": 0,
      "mmrc": 0
    },
    {
      "description": "Breathless only with strenuous exercise",
      "components": [
        {
          "factor": "mmrc",
          "points": 0,
          "present": true
        }
      ],
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Mahler DA, Wells CK",
        "doi": "10.1378/chest.93.3.580",
        "id": "mahler-1988",
        "pmid": "3342669",
        "source": "Chest. 1988;93(3):580-586",
        "title": "Evaluation of clinical methods for rating dyspnea"
      },
      "formula": "mmrc",
      "formula_expression": "modified MRC (mMRC) grade 0-4 as assigned by the caller; Mahler 1988 (not Bestall MRC 1-5)",
      "max_score": 4,
      "score": 0,
      "mmrc": 0
    }
  ]
}

Response

Field	Type	Description
`formula`	string	mmrc
`formula_expression`	string	Published grade rule
`mmrc`	integer	Caller-assigned modified MRC grade 0-4
`score`	integer	Same as mmrc
`max_score`	integer	4
`description`	string	Mahler 1988 wording for that grade
`components`	array	mmrc component
`citation`	object	Mahler and Wells 1988
`disclaimer`	string	Not a medical device

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "description": "Breathless only with strenuous exercise",
  "components": [
    {
      "factor": "mmrc",
      "points": 0,
      "present": true
    }
  ],
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Mahler DA, Wells CK",
    "doi": "10.1378/chest.93.3.580",
    "id": "mahler-1988",
    "pmid": "3342669",
    "source": "Chest. 1988;93(3):580-586",
    "title": "Evaluation of clinical methods for rating dyspnea"
  },
  "formula": "mmrc",
  "formula_expression": "modified MRC (mMRC) grade 0-4 as assigned by the caller; Mahler 1988 (not Bestall MRC 1-5)",
  "max_score": 4,
  "score": 0,
  "mmrc": 0
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

HTTP	Code	When
400	`invalid_mmrc`	mmrc must be an integer from 0 to 4. Returned before settlement; you are not charged.
400	`invalid_items`	POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
400	`invalid_item_count`	items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
400	`invalid_item`	each items entry must be a JSON object Returned before settlement; you are not charged.

Related tools

BODE — Sum Celli 2004 BODE points from BMI, FEV1 percent predicted, MMRC dyspnea, and 6-minute walk distance.

Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. Unpaid valid requests return HTTP 402 with a base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake and shared payment errors: Payments. Stdio MCP: /docs/mcp.

Guarantees

HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
Execution is timeout-bounded and concurrency-capped.
Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.